Process for manufacturing a laminated glazing

Abstract

A process for manufacturing a laminated glazing, in which a lamination interlayer is interposed between two substrates having a glass function, including: making a measurement of Young's modulus E on a sample of the interlayer, using a viscoanalyzer, by varying temperature and frequency while imposing a constant dynamic displacement; making a numerical treatment of curves obtained, using WLF (Williams-Landel-Ferry) equations, to establish a law E(f) governing behavior of a material constituting the interlayer sample at a given temperature; producing a numerical model based on a finite-element method in bending of a laminated glazing panel, wherein mechanical properties of the sample result from the preceding operations; comparing results of the numerical calculation with those obtained with analytical formulae in which participation of the interlayer in transferring shear in the laminated glazing is represented by a transfer coefficient ω; varying the transfer coefficient ω in the analytical formulae until results converge; and constructing a transfer function ω=f(E) by successive iterations.

The invention claimed is: 
     
       1. A process for manufacturing a laminated glazing, in which a lamination interlayer is interposed between two substrates having a glass function, the process comprising:
 making a measurement of Young's modulus E on a sample of the interlayer, using a viscoanalyzer, by varying temperature and frequency while imposing a constant dynamic displacement; 
 making a numerical treatment of curves obtained, using WLF (Williams-Landel-Ferry) equations, to establish a law governing behavior of a material constituting the interlayer sample at a given temperature; 
 producing a numerical model based on a finite-element method in bending of a laminated glazing panel, wherein mechanical properties of the sample result from the preceding operations; 
 comparing results of the numerical calculation with those obtained with analytical formulae in which participation of the interlayer in transferring shear in the laminated glazing is represented by a transfer coefficient ω; 
 varying the transfer coefficient ω in the analytical formulae until results converge; and 
 constructing a transfer function ω=f(E), wherein ω is the transfer coefficient and E is the Young's modulus of the interlayer, by successive iterations. 
 
     
     
       2. The manufacturing process as claimed in  claim 1 , wherein the temperature is varied between −20° C. and +60° C. 
     
     
       3. The manufacturing process as claimed in  claim 1 , wherein the frequency is varied between 5×10 −7  Hz and 3×10 −1  Hz. 
     
     
       4. An interlayer used in the process as claimed in  claim 1 , wherein the interlayer has a structuring function and is such that, for a wind load time of 3 s and for a use temperature between 0° C. and 20° C.:
 at 0° C., E>8×10 8  Pa; 
 at 10° C., E>3×10 8  Pa; 
 at 20° C., E>1×10 8  Pa. 
 
     
     
       5. An interlayer used in the process as claimed in  claim 1 , wherein the interlayer has a standard function and is such that, for a wind load time of 3 s and for a use temperature between 0° C. and 20° C.:
 at 0° C., E>1×10 8  Pa; and E≦8×10 8  Pa; 
 at 10° C., E>2×10 7  Pa and E≦3×10 8  Pa; 
 at 20° C., E>5×10 6  Pa; and E≦1×10 8  Pa. 
 
     
     
       6. An interlayer used in the process as claimed in  claim 1 , wherein the interlayer has a flexible or acoustic function and is such that, for a wind load time of 3 s and for a use temperature between 0° C. and 20° C.:
 at 0° C., E>1×10 7  Pa; and E≦1×10 8  Pa; 
 at 10° C., E>3×10 6  Pa and E≦2×10 7  Pa; 
 at 20° C., E>5×10 5  Pa and E≦5×10 6  Pa. 
 
     
     
       7. A laminated glazing comprising:
 at least a first substrate having a glass function; and 
 a second substrate having a glass function, 
 the substrates being laminated using an interlayer as claimed in  claim 4 . 
 
     
     
       8. A laminated glazing comprising:
 at least a first substrate having a glass function; and 
 a second substrate having a glass function between which a lamination interlayer is interposed, 
 the lamination interlayer manufactured by a manufacturing process as claimed in  claim 1 .